1. Field of the Technology
The present technology relates to a toner supply device and an image forming apparatus.
2. Description of the Related Art
An image forming apparatus equipped with a printer, a multifunction peripheral and the like forms an image using toner reserved in a developing device included in the image forming apparatus. There has been known a toner supply device which supplies toner to the developing device in a field of such an image forming apparatus. When toner in the developing device is consumed and reduced, the toner supply device supplies toner in a toner container included in the toner supply device to a toner hopper connected to the developing device, and the toner hopper supplies the supplied toner to the developing device sequentially.
Recently, a rotary-type toner supply device which supplies toner by rotating a toner container with a rotary drive source included in an image forming apparatus is the mainstream. In such a rotary-type toner supply device, toner is guided to a toner discharge port of the toner container by a rib in a spiral shape formed on an inner wall of the toner container by rotating the toner container and discharged from the toner discharge port so that the toner is supplied to the toner hopper. In such a rotary-type toner supply device, during image formation operation, the toner container is rotated and the toner in the toner container is thus maintaining high fluidity without being aggregated.
However, when the image formation operation is finished and power of the image forming apparatus is turned off, the rotation of the toner container is stopped and the toner in the toner container starts to aggregate by heat in the image forming apparatus. The longer the time in which the toner container is not rotating is, the more the toner in the toner container aggregates to adhere to an inner wall of the toner container. The toner strongly adhering to the inner wall rotates with the toner container even when the toner container starts to rotate again, so as not to be discharged from the toner container to remain. As a result, most of an unused toner remains in the toner container in some cases.
To cope with such a problem, for example, Japanese Unexamined Patent Publication JP-A 2000-147887 discloses a rotary-type toner supply device provided with a spiral scraping member fixed to an inner wall which rotates so as not to move in order to scrape off toner adhering to the inner wall of the rotary toner supply device.
The scraping member described in JP-A 2000-147887 is fixed, thus not rotating with the toner container, and the toner container and the toner in the toner container move relative to the scraping member. Therefore, when there is a small amount of toner in the toner container, it is possible to scrape off the toner with the scraping member for certain, however, when there is a large amount of toner remaining in the toner container, a load on the toner caused by the scraping member is large, so that the toner becomes deteriorated, which poses a problem. Moreover, there is a possibility that as counteraction to the load on the toner, a heavy load is also imposed on the scraping member so that the scraping member is broken.